Predation is usually referred to as a detrimental association. State any three positive roles that a predator plays in the ecosystem.

Discuss role of predators in an ecosystem,

Mention any two significant roles predation plays in nature.

Write any three imortant biotic components of an ecosystem.

Write two difference between autotrophs and hetetrophs. What role do they play in the energy flow of an ecosystem?

These questions consist of two statements each,printed as Assertion and Reason.While asnwering these questions you are required to chose any one of the following four responses. If both Assertion and Reason are true and Reason in correct explanation of Assertion. If both assertion and Reason are true but reason is not correct explanation of Assertion. If Assertion is true but Reason is false. If both Assertion and Reason are false. Assertion:Chlorine plays important role in dark reactions of photosynthesis. Reason: Chlorine plays an important role in process of seed germination.

If vec a , vec b , vec c , vec d are the position vector of point A , B , C and D , respectively referred to the same origin O such that no three of these point are collinear and vec a + vec c = vec b + vec d , than prove that quadrilateral A B C D is a parallelogram.

A magnet is suspended vertically from a fixed point by means of a spring, as shown in the figure. One end of the magnet hangs inside a coil of wire. The coil is connected in series with a resistance R. The magnet is displaced vertically a small distance D and the released. shown in the figure variation with time t of the vertical displacement d of the magnet from its equilibrium position. State and explain, by reference to electromagnetic induction, the nature of the oscillations of the magnet. Calculate the angular frequency omega_0 of the oscillations.

What are macronutrients that usually play the most importnt role in limiting plant growth glolally?